For all those that might purchase books from Amazon and sideload onto their Kobo please be aware that if you are running Windows 8 and download and use the Win 8 version, the book that is downloaded is fragmented into about 150 little bits, so it's impossible to sideload.

I had to uninstall the Win 8 version and install the Win 7 version which runs fine on Win 8 and also keeps the book whole in the "My Kindle Content" folder.

(Just make sure to remember to change the default folder location to your current one)